Method of making bearings



J1me 1931. J. 'r. LITTLETON. JR.. ETAL 1 7 Ea-HOD MAKING BEARINGS Filed 001;. 15, 1928 Patented June 2, 1931 UNITED STATES PATEN'll OFFICE JESSE T. LITTLETON', JR, OF COBNING, AND RAYMOND W. LILLIE, 01' ROCHELLE, NEW YORK METHOD OF BEARINGS This invention relates to bearings and the method of making them and more particularly to the production of composite bearings wherein a hard wear-resisting material such as glass is incorporated with a relatively soft, more or less pliant substance which may be machined to insure accurate centering of the bore of the bearing with relation to its exterior.

Heretofore attempts have been made to reduce glass bearings but owing to the inability to accurately locate the bore in the center of the bearing the use of such bearings has not proven wholly satisfactory. Moreover, much difiiculty has been experienced in preserving the accuracy of the bore due to the tendency of the material I to distort during its formation.

An object of the present invention is to reduce to a minimum the expense and labor incident to the proper maintenance of bearings, such as those used for supporting the shafts of electric motors and to improve the wear-resisting qualities of such bearings.

Another object is to produce accurate bores in low expansion wear-resisting bodies and to secure accurate location of the bores relatively to the exterior of bearings in which they are incorporated.

Still another object is to secure a hard. mechanical bearing surface and yet absorb the vibration which frequently accompanies the rotation of shafts in their bearings.

The above and other objects may be attained by practicing this invention which embodies among its featuresthe production of a-hard unyielding core, of wear-resisting material such as glass, having a low expansion coeificient and a smooth surfaced core of exact dimensions, the encasing of it in a relatively soft cushioning material, and the machining of the casing to accurately locate the bore with relation to the exterior of the'bearing. A glass suitable for use in producing such a core is .described and claimed in United States Letters Patent No. 1,304,623, ranted to Sullivan and Taylor.

In the awings;

Fig. 1 is a perspective view of a bearing :onstructed in accordance with this inven- Fig. 2 is a horizontal sectional view through Fig. 1;

Fig. 3 is a longitudinal sectional view taken on theline 3-3 of Fig. 2;

Fig. 4 is a top plan view of a mold used in producing the wear-resisting core;

Fig. .5 is a longitudinal sectional view. through the mold illustrated in Fig. 4;

Fig. 6 is a perspective view of a completed core; and

Fig. 7 is a longitudinal sectional view through a mold for shaping the yielding material around the core.

Referring to-the accompanying drawings, our lmproved bearing, designated generally 10, consists of a wear-resisting core 11 and a caslng 12, the former being provided with a bore 13 of the desired size. The bearing is preferably formed with an oil hole 14 which igmmunlcates' at its inner end with the bore In producing the core 11 above referred to, we provide a mold designated generally 15 which consists of a bed plate 16 and a pa1r of hinged mold halves 17. The bed plate 16 is provided in its upper side with a tapered recess 18 which is surrounded by an annular upwardly extending flange 19 forming a depression 20 in which a platen 21 is received. Each mold half 17 is provided at its lower end with a recess 22 to receive the flange 19 and the platen 20 and isalso formed with a mold cavity 23 which cooperates with the mold cavity of the opposite mold half to produce a mold chamber of the proper contour for the production of the core 11. Communicating with the chamber is a font 24 into which the molten glass from which the article is to be formed is introduced.

In order that the core 11 may be provided with a suitable longitudinal bore 13, a core pin 25 is seated in the tapered recess 18 with its upper end projected through an opening 26 in the platen 20 (Fig. 5). Formed in one of the mold halves is a radial opening 27 through which a radial core pin 28 extends,

and the inner end of said pin is received in a radial recess formed in the core pin 25. In this way the core pin 28 is retained in position to form a radial opening in the core 11 during its production. In forming the core 11 molten glass is introduced into the font 24, whereupon a plunger 29 is lowered into the font to expel the glass from the-font into the mold chamber. In order to prevent the checking of glass durin the formation of the core 11, we have ound it desirable to heat the core pins 25 and 28 prior to introducing them into the mold.

After pressing the core as above set forth the glass is removed from the mold and introduced into a suitable leer where it is annealed in the ordinary manner ,to relieve strains, the core pins 25 and 28 bein left in place during the annealing and coohng of the core. After cooling removal of the core pins may be easily accomplished as they are made from a material possessing a relatively high coetficient of expansion while the expansion of the glass is relatively low. Hence on cooling, the core pins will shrink away from their respective cavities andmay be readily withdrawn therefrom.

In order to provide the glass core with a yieldable outer casing 12 we provide a mold,

designated generally 30 which consists of a bed plate 31 having an integral upstanding wall 32 of an internal contour, corresponding to the shape of the finished bearing. A longitudinally extending stud 33 is secured in the bed plate 31 and is adapted to enter the bore 13 of the core 11 to hold the latter in proper position in the mold 30. A radially extending core pin 34 is then introduced through a radial opening 35 formed in the wall 30 and its inner end is received in the radial bore 14 which was formed in the core 11 by the core pin 28. Supported on the upper end of the core 11 is a cap 36 which is preferably of slightly larger diameter than the core 11 and provided in its under side with a recess 37 for the reception of the upper end of the stud 33.

After assembling the core 11 in the mold 30, as above'described, the material from which the casing 12 is to be made, such as phenol condensation products, is then introduced in powdered form, into the mold 30 around the core 11. A plunger 38, the outer contour of which corresponds to the internal configuration of the mold 30, is then introduced into the upper end of the mold to press the powdered material into compact form about the core, it being understood that this operation is carried on under the proper temperature and pressure conditions toconvert the powdered substance into a solid.

When using certain henol condensation products, I have found 3,000 pounds per square inch, at approximately 300 F. is suflicient for the purpose. After the pressing is completed the article that a ,pressure of is removed from the mold and machined to its proper external dimension.

It 'will be apparent that any inequalities in centering the bore 13 in the glass member 11 can be compensated for by a greater or lesser thickness in the portion of the casing member 12 which is in contact with that portion of the glass member 11, thus making it possible to produce a finished bearin 10 provided with a bore 13 that is dispose exactly centrally with respect thereto.

Owing to the smoothness which is characteristic of a finished lass surface, and the hardness of the glass, t ere will be very little friction between a bearing of the type embodying our invention and the shaft with which it is used. Consequently but very little heat will be developed and little or no lubrication will be required. Moreover, the period of service of such lubricants as may be used will be considerabl extended. In order that lubrication may be supplied, the bearing is provided with the bore 14 forming an oil hole, and by means of any well known oil feeding device, suflicient oil can be automatically supplied to the bearin s to provide proper lubrication for a cons't lerable period without attention.

Inasmuch as phenol condensation products have a conslderably (greater expansion than glass of the type in icated above, the materlal which forms the casing 12 will contract on setting and ti htly grip the core 11. However, if desire the latter ma be provided with rojecting lugs or fins w 'ch become embed ed in the casing 12 during the formation of the latter, so as to provide placement of the parts.

While we do not desire to be limited thereto, we have found that glass of the type set forth above is the most satisfactory material from which to produce the core 11, and that phenol condensation roducts are the most satisfactory materials or the outer casing. It will be obvious, however, that the component parts may be produced from other materials possessing the requisite properties. a

From the foregoing it will be apparent that we have not only devised a new and improved bearing which, when used in a machine, is comparable to the jewel in a watch but have also devised a new method of forming bearings. It will be obvious that these hearings and the method of making them may be varied in many ways, and we do not desire to be limited to the particular disclosure set forth herein, except as indicated by the scope of the following claims.

We claim: 1. The method of making bearings which consistsin forming a glass core with a shaftreceiving bore,vplacing said core in a mold, 30

surrounding the core with finely comminuted material and heating and exerting pressure on the finely comminuted material to form a solid casing around the core, and coolin to cause a contraction of said casing on sai core.

2. The method of making bearings which consists in forming a glass core with a shaftreceiving bore, placing said core in a mold, surroun ing the core with finely comminuted material,'and heating and exertin pressure on the finely comminuted materia to form a solid casing around the core and cooling to cause a contraction of said casing on said core, and machining said casing to center said bore.

3. The method of makin bearings which consists in forming from g ass of expansion coefiicient not greater than .0000040 a core with a shaft-receiving bore, lacing said core in a mold, surrounding t e core with finely comminuted material and heating and exerting pressure on the finely comminuted material to form a solid casing around the core and cooling to cause a contraction of said casing on said core, and machining said casing to center said bore.

4. The method of making bearings which consists in forming a glass core with a shaft receiving bore, placing said core in a mold surroun ing the core with a owdere phenol condensation product an heatin and exerting pressure on the powdere phenol condensation product to form a solid casing around the core and cooling to cause a contraction of said casing on said core.

5. The method of making bearings which consists in forming a glass core with a shaftreceiving bore, placing said core in a mold surroun ing the core with a phenol condensation product an heatin and exerting pressure on the powdere phenol condensation product to form a solid casing around the core and cooling to cause a contraction of said casing on said core,

{121d machining said casing to center said 6. The method of makin bearings which consists in forming from g ass of expansion coefiicient not greater than .0000040 a core with a shaft-receiving bore, placing said core in a mold, surrounding the core with a powdered phenol condensation product and eating and exerting pressure on the owdered phenol condensation product to orm a solid casing around the core and coolin to cause a contraction of said casing on sai core, and'machining said casing to center said bore.

JESSE T-. LITTLETON, JR. RAYMOND W. LILLIE.-

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